U.S. patent application number 11/616552 was filed with the patent office on 2008-07-03 for method for making a tea extract and a tea extract.
This patent application is currently assigned to Conopco, Inc., d/b/a Unilever, Conopco, Inc., d/b/a Unilever. Invention is credited to Shi-Qiu Zhang.
Application Number | 20080160135 11/616552 |
Document ID | / |
Family ID | 39450918 |
Filed Date | 2008-07-03 |
United States Patent
Application |
20080160135 |
Kind Code |
A1 |
Zhang; Shi-Qiu |
July 3, 2008 |
Method for Making a Tea Extract and a Tea Extract
Abstract
Shelf stable and ready-to-drink tea beverages are described. The
tea beverages have excellent color and flavor characteristics and
are prepared from a tea extract that has been made with both cold
brew and standard tea leaf. The tea beverages maintain excellent
characteristics in the absence of preservatives and caramel.
Inventors: |
Zhang; Shi-Qiu; (Tenafly,
NJ) |
Correspondence
Address: |
UNILEVER PATENT GROUP
800 SYLVAN AVENUE, AG West S. Wing
ENGLEWOOD CLIFFS
NJ
07632-3100
US
|
Assignee: |
Conopco, Inc., d/b/a
Unilever
Englewood Cliffs
NJ
|
Family ID: |
39450918 |
Appl. No.: |
11/616552 |
Filed: |
December 27, 2006 |
Current U.S.
Class: |
426/52 ; 426/435;
426/597; 426/655 |
Current CPC
Class: |
A23F 3/18 20130101; A23F
3/163 20130101; A23V 2002/00 20130101; A23V 2002/00 20130101; A23V
2250/214 20130101 |
Class at
Publication: |
426/52 ; 426/435;
426/655; 426/597 |
International
Class: |
A23F 3/16 20060101
A23F003/16; A23F 3/10 20060101 A23F003/10; A23F 3/34 20060101
A23F003/34 |
Claims
1. A method for making a tea extract comprising, in no particular
order, (a) preparing a mixture of cold brew tea leaf with tea leaf,
and extracting the mixture of tea leaf with water to produce tea
percolate comprising tea solid, or (b) extracting cold brew tea
leaf to produce a cold brew percolate, and extracting tea leaf to
produce leaf percolate and combining the cold brew percolate and
leaf percolate to produce the tea percolate with tea solid, or (c)
both; and (d) optionally, producing a tea extract by heating the
leaf percolate, the cold brew percolate or both prior to combining,
or by heating the tea percolate with tea solid, the tea percolate
with tea solid, the tea extract or mixture thereof, when diluted
with water, is suitable to make a ready-to-drink tea beverage
comprising 0.001 to about 6% by weight tea solid and that is shelf
stable for at least about 25 weeks.
2. The method according to claim 1 wherein the tea percolate
comprising tea solid is made according to step a and the tea
percolate comprising tea solid is heated to produce the tea
extract.
3. The method according to claim 1 wherein the tea extract
comprises from about 0.5 to about 55% by weight tea solid.
4. The method according to claim 1 wherein the cold brew tea was
prepared from tea leaf having been treated with tannase
5. The method according to claim 2 wherein the ready-to-drink tea
beverage is shelf stable for about 35 weeks.
6. The method according to claim 2 wherein the ready-to-drink tea
beverage is shelf stable for about 39 weeks.
7. The method according to claim 1 wherein the cold brew tea leaf
and tea leaf are at a weight ratio from about 80:20 to about
20:80.
8. The method according to claim 1 wherein the cold brew tea leaf
and tea leaf are at a weight ratio from about 70:30 to about
30:70.
9. The method according to claim 1 wherein the cold brew tea leaf
and tea leaf are at a weight ratio from about 40:60 to about
60:40.
10. The method according to claim 2 wherein heating is conducted at
a temperature from about 65 to about 99 degrees centigrade and at a
flow rate from about 1 to about 3 ml/minute.
11. The method according to claim 10 wherein heating is conducted
free of oxidative conditions.
12. A tea extract made according to the method of claim 1.
13. A ready-to-drink tea beverage made with the tea extract of
claim 12.
Description
FIELD OF THE INVENTION
[0001] The present invention is directed to a method for making a
tea extract and a tea extract. More particularly, the present
invention is directed to a method for making a tea extract from a
mixture of cold and hot brew tea leaves. The resulting tea extract
unexpectedly can be used to make a tea beverage that has excellent
flavor, stability and color characteristics, and especially, when
the tea extract is used to make a ready-to-drink tea beverage.
Moreover, the excellent characteristics are surprisingly achieved
when the tea beverage is substantitally free of preservative and
artificial color, like caramel.
BACKGROUND OF THE INVENTION
[0002] Excluding water, tea is the most popular beverage consumed
by man. Tea is very refreshing, can be served either hot or cold,
and has been made commercially available for many years.
Lipton.RTM., for example, is the world's leading brand of tea, made
available in over 110 countries by Unilever.
[0003] Today, modern scientists are exploring the exciting
potential of tea, which has a unique combination of natural
antioxidants known as flavonoids that can include catechins,
flavonols and flavonol glucosides. Taken regularly, tea can help
improve vascular function, combat fatigue, reduce cholesterol
levels and increase feelings of vitality
[0004] Antioxidants found in tea are believed to reduce the risk of
cancer. In fact, studies indicate that antioxidants can lower the
risks of cancer in the upper digestive tract, colon, rectum,
pancreas and breasts.
[0005] Furthermore, and in our very hectic world, many consumers
prefer teas that are ready-to-drink. Such teas, however, often
require preservatives and/or artificial colorants (like caramel)
that certain tea manufacturers require in order to deliver a
product that appears to have stability and color attributes
consistent with tea made by leaf infusion. Use of preservatives and
artificial colorants, however, can discourage consumers from
consuming tea since preservatives and artificial colorants are
often associated with beverages that are not considered to be
beneficial to one's health
[0006] It is of increasing interest to deliver a tea beverage (and
especially a ready-to-drink tea beverage) that has flavor,
stability and color attributes consistent with those found in tea
made by leaf infusion while at the same time being free of
preservatives and artificial colorants. This invention, therefore,
is directed to a method for making a tea extract and a tea extract
whereby the tea extract unexpectedly can be used to make a
ready-to-drink tea beverage with flavor, stability and color
attributes consistent with the attributes of tea made by leaf
infusion, and surprisingly, substantially free of preservatives and
artificial colors.
Additional Information
[0007] Efforts have been disclosed for making tea beverages. In
European patent No. 0 939 593 B1, tea beverages with high amounts
of catechins are described
[0008] Other efforts have been disclosed for making tea beverages.
In U.S. Pat. No. 6,780,454, cold water infusible tea leaf and
beverages made from the same are described.
[0009] Still other efforts for making beverages have been
disclosed. In U.S. Patent Application No. 2005/0123660 A1, tea
beverages with improved flavor are described.
[0010] None of the additional information above describes a method
for making a tea extract and a tea extract whereby the tea extract
is prepared from a mixture of cold and hot brew tea leaves further
whereby the tea extract can be used to make a tea beverage that
unexpectedly has excellent flavor, stability and color
characteristics while at the same time being substantially free of
preservatives and artificial colors.
SUMMARY OF THE INVENTION
[0011] In a first aspect, the present invention is directed to a
method for making a tea extract comprising, in no particular order,
the steps of: [0012] (a) preparing a mixture of cold brew tea leaf
with tea leaf, and extracting the mixture of tea leaf with water to
produce tea percolate comprising tea solid, or [0013] (b)
extracting cold brew tea leaf to produce a cold brew percolate, and
extracting tea leaf to produce leaf percolate and combining the
cold brew percolate and leaf percolate to produce the tea percolate
with tea solid, or [0014] (c) both; and [0015] (d) optionally,
producing a tea extract by heating the leaf percolate, the cold
brew percolate or both prior to combining, or by heating the tea
percolate with tea solid,
[0016] the tea percolate with tea solid, the tea extract or mixture
thereof, when diluted with water, is suitable to make a
ready-to-drink tea beverage comprising 0.001 to about 6% by weight
tea solid and that is shelf stable for at least about 25 weeks.
[0017] In a second aspect, the present invention is directed to the
tea extract made via the method defined in the first aspect of this
invention.
[0018] In a third aspect, the present invention is directed to a
tea beverage made from the tea percolate with tea solids, tea
extract or mixture thereof as defined in the second aspect of this
invention.
[0019] Extracting, as used herein, means contacting leaf with
water, and preferably, hot water in order to produce a percolate.
Tea percolate with tea solids, as used herein, is meant to mean the
liquid with tea solid product recovered after extracting tea leaf
and cold brew tea leaf with water (preferably water with less about
200 ppm total dissolved solids with Mg, Zn and Al collectively less
than 20 ppm, and preferably, less than 10 ppm in the water) where
the total flavonoid level in the percolate is substantially the
same as the flavonoid level in dry raw material tea leaf used to
deliver tea leaf and cold brew tea leaf. Tea extract means the
liquid and tea solid product resulting from the heating of the tea
percolate with tea solids (about 0.5 to about 50% by weight tea
solids based on total weight of the tea percolate with tea solids
and including all ranges subsumed therein) where the tea extract
comprises from about 0.5 to about 55% by weight tea solids based on
total weight of the tea extract and including all ranges subsumed
therein. Tea beverage as used herein is meant to include a beverage
ready to consume such as a ready-to-drink tea beverage, and
especially, a ready-to-drink black tea beverage. Substantially free
of preservative and artificial colors means less than about 0.05%
by weight (combined solids) based on total weight of the beverage
composition, and preferably, from about 0.001 to about 0.04% by
weight, and most preferably, no preservative and no artificial
colors. Cold brew tea leaf means green tea leaf (i.e., Camellia
sinesis) having been macerated and treated with tannase for a time
long enough to allow the leaf to ferment and generate gallic acid
and theaflavin wherein fermentation is continued in the presence of
an oxygen containing substrate at an amount sufficient to activate
endogeneous peroxidases further wherein the resulting fermented
leaf is dried to yield cold brew tea leaf often having from about 2
to about 6 times higher levels of isotheaflavin, epitheaflavic acid
and theaflagallin than tea leaf. Such a cold brew tea leaf is
described in U.S. Pat. No. 6,780,454, the disclosure of which is
incorporated herein by reference.
[0020] Tea leaf as used herein means tea leaf from Camellia sinesis
that has not been treated with tannase and an oxygen containing
substrate, and preferably, black tea leaf made commercially
available by Unilever. Shelf stable as used herein means having an
initial Hunter Haze Value of less than about 25, an initial
darkness value (L) from about 15 to about 45, an initial redness
value (a) from about 10 to about 40, and an initial yellow value
(b) from about 8 to about 30 and final values that preferably are
not more than 6, and most preferably, not more than 3 units off of
the initial values after being stored at about ambient temperature
for at least about 25 weeks while in light for about 12 hours each
day, where all values can be obtained with a Hunter Lab DP 9000
Spectrophotometer and at ambient temperature.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0021] There is no limitation with respect to how the tea percolate
comprising tea solids is made as long as the same is the product of
water being contacted with cold brew tea leaf and tea leaf. In a
preferred embodiment, however, the tea percolate comprising tea
solids is the result of an extraction process that extracts cold
brew tea leaf and tea leaf that have been mixed together (including
cold brew tea leaf and tea leaf extractions conducted with leaf in
a tea bag). There is no limitation with respect to how the cold
brew tea leaf and tea leaf are extracted, but column extraction is
often preferred. Typically, the extraction is done at a temperature
from about 20.degree. C. to about 99.degree. C., and preferably,
from about 25.degree. C. to about 95.degree. C., and most
preferably, from about 40.degree. C. to about 60.degree. C.,
including all ranges subsumed therein. The extraction may be done
at any pressure as long as a tea percolate with tea solids may be
produced. Typically, however, the pressure at which the extraction
is conducted is about atmospheric and often the flow rate of water
during the extraction process is from about 75 to 200 ml/min, and
preferably, from about 80 to 175 ml/min, and most preferably, from
about 110 to about 140 ml/min, including all ranges subsumed
therein.
[0022] Regarding the amount of cold brew tea leaf and tea leaf
used, typically a weight ratio from about 80:20 to about 20:80, and
preferably, from about 70:30 to about 30:70, and most preferably,
from about 40:60 to about 60:40 is used (cold brew tea leaf:tea
leaf, respectively), including all weight ratios subsumed therein.
The ratio selected can be used to make a mixture of tea leaf and
cold brew tea leaf which is extracted to make the desired tea
percolate with tea solids, or the cold brew tea leaf and tea leaf
may be extracted separately after which the resulting cold brew
percolate and leaf percolate (respectively) may be combined to
produce the desired tea percolate with tea solids If the latter
approach is desired, the ratio of cold brew percolate and leaf
percolate, after mixing, should be consistent with what would have
been tea percolate with tea solids made by extracting a mixture of
cold brew tea leaf with tea leaf at the above identified leaf
ratios. Often, the tea percolate with tea solids has from about 0.5
to about 50%, and preferably, from about 2.5 to about 25%, and most
preferably, from about 3.0 to about 10% by weight tea solids,
including all ranges subsumed. Such a tea, percolate with tea
solids may be polished to remove molecules that have a molecular
weight (Mw) greater than about 3,000, and such a polishing step is
meant to include a standard centrifuge-based separation technique
and filtering technique.
[0023] When making a tea beverage, the tea percolate with tea
solids may be diluted with water. The water may be still or gas
comprising (e.g., carbonated) and the tea beverage (i.e.,
ready-to-drink tea beverage) made will typically comprise from
about 0.001 to about 6% by weight tea solids (including all ranges
subsumed therein) and be shelf stable for at least about 25
weeks.
[0024] In a preferred but optional embodiment, a tea extract may be
produced by heating the leaf percolate, the cold brew percolate or
both prior to combining or by heating the tea percolate with tea
solids. Thus, tea extract as used herein means a product comprising
what is produced by heating percolate with tea solids, or a product
produced by heating tea leaf percolate, cold brew percolate or
both, prior to combining. In a more preferred optional embodiment,
at least the leaf percolate is heated. In a most preferred optional
embodiment, the tea-percolate with tea solids is heated to produce
tea extract.
[0025] When making a preferred tea beverage, tea extract made by
heating tea percolate with tea solids may be diluted with water.
The water may be still or gas comprising and the tea beverage
(i.e., ready-to-drink tea beverage) made will typically comprise
from about 0.01 to about 6% by weight tea solids and be shelf
stable for at least about 25 weeks, and preferably, at least about
35 weeks, and most preferably, at least about 39 weeks. The
preferred ready-to-drink tea beverage preferably comprises from
about 0.02 to about 3%, and most preferably, from about 0.1 to
about 0.6% by weight tea solids, including all ranges subsumed
therein. Moreover, the preferred ready-to-drink tea beverage is
preferably made by diluting tea extract with cold water (e.g.,
about 20 to 28.degree. C.) so that the tea beverage may preferably
be hot filled or packed in a desired consumer friendly package and
as described in U.S. Pat. No. 5,529,796, the disclosure of which is
incorporated herein by reference.
[0026] When heating percolate like the tea percolate with tea
solids, such a step is often done in a manner (which is free of
oxidative conditions, for example, less than 2 ppm dissolved oxygen
in the percolate) to induce Maillard reactions, glycosylamine
production, glycosylamine rearrangements, amino acid and/or protein
interactions with carbohydrates found in tea leaf, or a combination
thereof.
[0027] Often, the heating is conducted at a temperature from about
65 to about 99.degree. C., and preferably, from about 70 to about
98.degree. C., and most preferably, from about 78 to about
97.degree. C., including all ranges subsumed therein. The flow rate
of percolate during heating is typically from about 1 to about 3
ml/minute, and preferably, from about 1.3 to about 2.6 ml/minute,
and most preferably, from about 1.5 to about 2.2 ml/minute,
including all ranges subsumed therein. In an especially preferred
embodiment, the heating step takes place in an apparatus
substantially free of oxygen, and most especially, free of
conditions that will cause oxidation of tea components within the
percolate being heated to make extract.
[0028] The ready-to-drink tea beverage made according to this
invention will preferably have a Hunter Haze value less than about
20, and most preferably, less than about 15, a darkness value (L)
from about 20 to about 40, and preferably from about 25 to about
35, and a redness value (a) from about 15 to about 38, and most
preferably, from about 25 to about 35, and a yellow value (b) from
about 15 to about 28, and most preferably, from about 20 to about
26, including all ranges subsumed therein and after about 35 weeks,
and most preferably, after about 39 weeks.
[0029] It is within the scope of this invention to employ well
known additives when making the ready-to-drink tea beverages of
this invention. Such additives include chelator, sequestrant,
flavor, vitamin, sweetener, fruit juices, herbal/botanical
extracts, surfactant (like sorbitan monolaurate and sorbitan
monoplamitate), acidulant (to achieve a pH between about 2.5 to
6.5), bitterness blockers, additional natural tea components (like
catechins, caffeine) and the like. When employed, such optional
additives, collectively, make up less than about 35% by weight of
the total weight of the beverage.
[0030] The packaging which may be used for the ready-to-drink
beverage product described herein is limited only to the extent
that it is consumer safe and friendly. Often such packaging is a
bottle (PCT or glass), can or tetrapak box.
[0031] The examples below are provided to facilitate an
understanding of the invention and are not intended to limit the
scope of the claims.
EXAMPLE 1
[0032] A mixture of black tea leaf (Camellia sinesis) and cold brew
tea leaf was made, weight ratio about 55:45, respectively. The
resulting mixture was extracted with water at a flow rate of about
125 ml/min and at a temperature of about 50.degree. C. to produce a
tea percolate with tea solids. The same was subjected to a
centrifugation step to remove molecules with a molecular weight
(Mw) greater than about 3,000 (6000G for less than about 30 sec)
and the resulting tea percolate with tea solids had a solids level
of about 3.5% by weight.
[0033] The tea percolate with tea solids was heated (about
88.degree. C.) under sealed conditions, in the absence of oxygen
and at a flow rate of about 1.8 ml/minute. The resulting tea
extract was diluted with water to produce the ready-to-drink tea
beverages consistent with this invention (0.28% by weight tea
solids and free of preservatives and artificial color).
EXAMPLE 2
[0034] The method of Example 1 was repeated except that 100% black
tea leaf was used in lieu of a mixture of black tea leaf and cold
brew tea leaf and the resulting tea percolate with tea solids was
not heated as described in Example 1. The ready-to-drink tea
beverages made were similar to conventional ready-to-drink tea
beverages made commercially available, and the beverages did
contain artificial colors (about 0.002% by weight).
EXAMPLE 3
[0035] Skilled panelists assessed the ready-to-drink teas made in
the manner described in Examples 1 and 2 as well as commercially
available ready-to-drink teas made with preservatives (e.g.,
sorbates) and artificial colors (e.g., caramel).
[0036] All panelists concluded that the ready-to-drink teas made
according to Example 1 (free of preservatives and artificial
colors) had better taste characteristics and the look of
conventional ready-to-drink teas with preservatives and artificial
colors. Moreover, the Haze, L, a and b values of the ready-to-drink
beverages made according to Example 1 were consistent those of
conventional ready-to-drink teas with preservatives and artificial
colors and shelf stable for at least about 39 weeks.
[0037] The results indicate that the ready-to-drink tea beverages
made according to this invention had better flavor, and stability
and color attributes consistent with artificially colored
ready-to-drink tea beverages.
* * * * *